A frequently recurring fantasy that I have heard from many people is the notion that we don’t need to worry about the population bomb or the depletion of resources on earth because many people will soon be able to live in outer space. Under this rosy scenario, asteroids, moons and other planets in our own solar system will provide abundant resources to support earth’s growing population and economy.

     It is a comforting delusion for people like me who grew up reading science fiction. I don’t rule out the possibility that some day a significant portion of humanity might live in non-terrestrial locations. But moving people to outer space is not a solution to the major environmental crises which we face in the next 20 to 50 years.

     It does not take an advanced degree in rocket science to explain why this is true. We live on a planet that is warm, wet, bathed in a breathable atmosphere, and rich in the organic compounds created by life on earth. The gravity is right for us as well. These are conditions that are almost ideal for humans to survive and thrive. That is not too surprising, because billions of years of evolution have eliminated organisms that cannot survive well in this environment.

     All other locations in our solar system, on the other hand, are deadly to an unprotected human. We find hard vacuums, or atmospheres which lack oxygen or which are toxic to us. There are temperatures of extreme cold or extreme heat. In some places the gravity will crush us, while in other places we are likely to go flying off into space with one jump. Sure, we can go to some of these places if we carry our environment with us, but outer space is not an easy place to visit, much less live on a permanent basis.

     Cosmic rays are another huge barrier to humans in space. Once we move away from the earth’s protective atmosphere and magnetic field, we are subjected to cosmic rays that tear up our genetic and cellular structures. While our bodies can absorb and repair some of this type of damage, we cannot survive there for years and years. This is a huge problem even for a human trip to Mars, our nearest planetary neighbor. To live elsewhere we need protection, and as a practical matter, this requires a planet or asteroid to shield us

    Then there is the problem of building a self-sustaining enclosed environment, where all waste products can be recycled and reused without the help of ongoing inputs from the earth’s biosphere. To date, no one has been able to live in such a self-contained system for very long without being overwhelmed by the waste products, even here on Earth. In space, or on another planet or asteroid, the problem is even more difficult to solve.

     There are other problems with trying to use outer space as a solution to the problems on Earth. Using existing technology, it takes a huge amount of fuel to lift even one person off the Earth and into low earth orbit. It takes even more fuel to move that person to the moon or Mars or some other location where there is gravity, protection from cosmic rays, and an opportunity to build a place to live. Trying to launch just one percent of the earth’s population into orbit (which amounts to over 60 million people) would destroy the Earth’s atmosphere for centuries to come. That one percent would quickly be replaced by the existing birth rate. We are not going to solve the problem of overpopulation that way.

     I have talked to some of the people who believe that space is the solution to environmental and population problems. They argue that science will overcome all of the barriers to human expansion into space. But while their faith in science is touching, it is not well founded in the short term.

     Look at our history. We have taken a lush, fertile planet that is ideal for human survival, and are systematically destroying it. We are turning rich productive land into deserts on a massive scale. We are stripping the oceans of their life. We are transforming rain forests into seas of mud. In a few short decades, we have drained fossil aquifers that took thousands of years to form. We have demonstrated our total inability to wisely manage a resource rich environment like the planet Earth.

     Given our exceedingly poor track record on Earth, there is no reason to believe that we can guarantee our survival by moving to the severe and inhospitable environments found in places other than the Earth. For now, blasting off into space will not solve our problems on this planet. We need to learn how to live sustainably on the planet we have. We have a lot to learn.

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